Pam Bennett, Barb Bloetscher, Joe Boggs, Jim Chatfield, Erik Draper, Dave Dyke, Dave Goerig, Tim Malinich, Jane Martin, Amy Stone, and Curtis Young
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April 27, 2006
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This is the fourth 2006 edition of the Buckeye Yard and Garden Line (BYGL).
BYGL is developed from a Tuesday morning conference call of Extension
agents, specialists and other contributors in Ohio.
BYGL is also made available on the Internet from the Ohio State University
Horticulture and Crop Science (HCS) in Virtual Perspective website
(http://bygl.osu.edu). Additional fact sheet information on any of
these articles may be found through the OSU fact sheet database (http://plantfacts.osu.edu).
BYGL is a service of OSU Extension and is aided by major support
from the Ohio Nursery and Landscape Association (ONLA), with additional
funding from the Ohio Chapter of the International Society of Arboriculture
(ISA) to the OSU Extension Nursery Landscape, and Turf Team (ENLTT).
Participants in the April 25, 2006 conference included: Pam Bennett (Clark); Barb Bloetscher (Entomology/C. Wayne Ellett Plant and Pest Diagnostic Clinic (CWEPPDC)); Joe Boggs (Hamilton/Piketon); Erik Draper (Geauga); Tim Malinich (Cuyahoga); Jane Martin (Franklin); Dave Shetlar (Entomology); Amy Stone (Lucas); Nancy Taylor (Plant Pathology/CWEPPDC); Curtis Young (Allen); and Randy Zondag (Lake). .
Additional factsheet information on any of these articles may be found
through the OSU Factsheet Database (http://plantfacts.ohio-state.edu/)
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WEATHER WATCH
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BYGLers across Ohio were bracing for the prediction of temperatures dipping below the freezing mark Tuesday evening during this week's conference call. The sun returned for those enjoying the springtime blooms.
| Weather Station |
Region of Ohio |
Ave. High Temp F | Ave. Low Temp F | Ave. Temp F | Normal Ave. Temp F | Total Precip " | Normal Precip " | | Perry |
NE |
60.6 |
40.6 |
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NA |
4.79" |
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| Hoytville |
NW |
66.2 |
39.9 |
52.9 |
48.1 |
1.75" |
2.81" |
| Columbus |
Central |
68.9 |
44.5 |
56.5 |
50.3 |
2.29" |
3.27" |
| Miami |
SW |
69.2 |
45.1 |
56.9 |
50.3 |
3.19" |
2.90" |
| Jackson |
South |
71.5 |
43.5 |
57.2 |
51.6 |
4.35" |
3.36" |
For a link to the OARDC Weather Stations, check out: http://www.oardc.ohio-state.edu/centernet/weather.htm
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HORT SHORTS
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GDD (GROWING DEGREE DAYS)
GDD is a measure of the daily maximum and minimum temperature and directly relates to growth and development of plants and insects. The GDD of any zip code location in Ohio is estimated using the GDD of ten OARDC weather stations and available on the web at the site below.
The range of GDD accumulations in Ohio from north to south is 184 to 391. Following is a report of GDD for several locations around Ohio as of April 26, 2006: Painesville, 184; Cleveland, 198; Toledo, 218; Youngstown, 221; Lima, 242; Wooster, 253; Coshocton, 277; Columbus, 304; Springfield, 269; Dayton, 289; Cincinnati, 329; Ironton, 374; Portsmouth, 376; and Piketon, 391.
To put these GDD accumulations into perspective, the following is an abbreviated listing of plant and insect species with their respective phenological event and average GDD accumulations at which these events occur. Due to variations in weather, temperature, humidity, etc., these events may occur a few days earlier or later than predicted by the average GDD. By looking at a city, town, or village near you from the above list, or visiting the above web site, you can see what could be taking place in the landscape around you.
Weeping Higan cherry, full bloom, 179; Koreanspice viburnum, first bloom, 185; Regent serviceberry, first bloom, 186; Japanese flowering crabapple, first bloom, 189; Eastern redbud, first bloom, 191; gypsy moth, egg hatch, 192; Koreanspice viburnum, full bloom, 205; azalea lace bug, egg hatch, 206; 'Spring Snow' crabapple, full bloom, 209; common flowering quince, full bloom, 214; birch leafminer, adult emergence, 215; 'Coralburst' crabapple, first bloom, 217; elm leafminer, adult emergence, 219; common chokecherry, full bloom, 221; alder leafminer, adult emergence, 224; honeylocust plant bug, egg hatch, 230; common lilac, first bloom, 234; Ohio buckeye, first bloom, 245; eastern redbud, full bloom, 245; common horse chestnut, first bloom, 251; hawthorn lace bug, adult emergence, 253; hawthorn leafminer, adult emergence, 260; flowering dogwood, first bloom, 263; red buckeye, first bloom, 265; blackhaw viburnum, first bloom, 269; imported willow leaf beetle, adult emergence, 274; Sargent crabapple, full bloom, 298; red horsechestnut, first bloom, 304; pine needle scale, egg hatch - 1st generation, 305; Cooley spruce gall adelgid, egg hatch, 308; eastern spruce gall adelgid, egg hatch, 308; common lilac, full bloom, 315; Winter King hawthorn, first bloom, 328; lilac borer, adult emergence, 330; Ohio buckeye, full bloom, 374; holly leafminer, adult emergence, 375; Vanhoutte spirea, full bloom, 406; and euonymus scale (first generation), egg hatch, 406.
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PLANT PHENOLOGY
Joe Boggs noted that the flowering dogwoods (Cornus florida) and crabapples (Malus spp.) were in full bloom at this time.
In central Ohio, Pam Bennett and Jane Martin noted the following plants in full bloom: redbud (Cercis canadensis), flowering dogwoods, common lilacs (Syringa vulgaris), leatherleaf and Koreanspice viburnum (Viburnum rhytidophyllum and carlesi respectively), crabapples, oaks (Quercus spp.), and flowering quince (Chaenomeles speciosa),. Ohio buckeye (Aesculus glabra) flower buds were just beginning to swell.
In the Lima area, Curtis Young said that the forsythia were still in bloom as well as Koreanspice viburnums, crabapples, flowering quince, flowering dogwood, some of the hollies (Ilex spp.) and barberries (Berberis spp.), and the hawthorns (Crateagus spp.) in the wooded areas.
Amy noted that the similar plants were in bloom in the Toledo area and added that the Oregon grapeholly (Mahonia aquifolium) was in full bloom.
Randy Zondag noted that crabapples and apples were not open at this time but forsythia (Forsythia spp.) were in full bloom and magnolias (Magnolia spp.) and serviceberry (Amelanchier spp.) were waning.
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PLANTS OF THE WEEK
Read all about perennials and landscape trees and shrubs in the publications "Perennial Plants for Ohio" and "Landscape Plants for Ohio" published by the ONLA. The descriptions and photographs of plants were written and produced by the OSU ENLT Team along with other industry plant lovers. These full-color publications are available at http://Buckeyegardening.com for $5.00. Click on "garden store" and then "ONLA plant guides." ONLA members can purchase these in quantities at a reduced price at http://onla.org
*PERENNIAL PLANT OF THE WEEK. Foamflower (Tiarella spp.) - This beautiful native (T. cordifolia) just finished an incredible bloom spree in Clifton Gorge (Greene County) this past week. The cultivated plants are just beginning to bloom in central Ohio gardens. This outstanding plant is excellent for shade gardens and grows around 6-12" tall depending upon the cultivar. The delicate flower clusters on spikes bloom in mid-spring and appear to be a floating cloud of foam on top of the foliage. New cultivars have been developed for foliage shape, color and variegation. 'Ninja' has emerald green leaves with black markings on the veins and fragrant coral flowers and 'Iron Butterfly' has really cool, dissected leaves with purple-bronze markings along the veins.
*WOODY PLANT OF THE WEEK: Eastern redbud (Cercis canadensis). This wonderful native understory tree is now showing its spectacular season of bloom throughout much of Ohio. Remember to provide partial shade to avoid stressing the plant. Otherwise Botryosphaeria dieback and Verticillium wilt disease often result in branch dieback and tree decline.
From "Landscape Plants for Ohio" "Eastern redbuds are one of our best small (15-20 foot) native trees for spring flowering, as lavender-pink flowers emerge before the leaves in April for a graceful show. Heart-shaped green leaves, zig-zag stems, and layered branching are all good ornamental traits. 'Lavender Twist' is a small weeping cultivar. 'Forest Pansy', with vivid purple leaves which soften with the season, is a popular Zone 5 cultivar and is reported to be more tolerant of more sunny sites. The variety 'Alba' is a white-flowered cultivar that is gaining in popularity.
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SECREST SIGHTINGS
When we think of maples, flowers are probably not the first thing that comes to mind. Yet many maples have wonderful flowers. Landscapes, streetscapes and woodlands were brightened in northeast Ohio this past week by the light-yellow sunny displays of pendulous sugar maples' corymbs. Norway maple, with its chartreuse five-petaled blooms, are spectacular enmasse and even better if you look at the flowers up close. For an intriguing contrast, take a look at the emerging shiny burgundy leaves of 'Schwedleri' and 'Crimson King' Norway maples paired with the chartreuse flowers. And, nothing could be more delicate than the pale yellow green petals and anthers and the fine-featured salmon-colored filaments of Acer tschonoskii var. koreana next to the rhododendron valley at Secrest Arboretum this past weekend.
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GARLIC MUSTARD - GET IT NOW - AND THEN LATER TOO
Over the years, garlic mustard (Alliaria petiolata) has achieved a nice foothold in many of Ohio's natural areas and is in home gardens as well. It is believed that this invasive plant was brought to the US for its culinary benefits--it has a garlic-like scent.
Garlic mustard is a biennial that produces dark purple and green, scallop-edged leaves in rosettes the first year and shoots up to about 2' tall the 2nd year. Clusters of small white flowers (2nd year) appear at the tips around late April. Seed pods hold around 16 seeds; large plants might have up to 150 pods or more. In large infestations, over 20,000 seeds per year are possible. Seeds remain viable in the soil for up to 5 years.
Control of this pest is not easy as multiple options may be required, depending on the size of infestation. Over the years, research has shown the following tips help with eradication: 1). When cutting the garlic mustard, cut the plant as close to the ground as possible; 2). When pulling, and if in bloom, bag the debris as it continues to form seeds, even while laying on the ground; and 3). When using a non-selective herbicide, apply in the fall (October-November) when the possibility of damaging other plants is minimal. With all options, try to disturb the soil as little as possible to prevent further seed emergence. For more details, refer to the following web site: www.ipm.msu.edu/garlicMge.htm
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BUG BYTES
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RAINING MAGGOTS
Several complaints have surfaced this spring of "tiny white worms" falling from pin oak trees by the hundreds. These are often the larvae of a gall midge, Contarinina spp., Family Cecidomyiidae.
The adult flies emerge in early spring and lay clusters of eggs in the flower bracts of the pin oaks. As the oval, 1/16" long white larvae develop, they feed on the flowers and may crawl onto the unfurling leaves, however, unlike other gall midges, these maggots do not damage the leaves, but flip and land on the ground to pupate. The following spring they emerge as adults, mate, and continue the cycle. Although this species does not appear to damage the oak flowers, the Contarinia species contain some harmful pests, such as the Douglas-fir needle midge, Contarinia pseudotsugae and the newly identified Swede midge C. nasturtii, which causes distortion of cole crops.
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BEES BURROWING
The PPDC has received several questions concerning "swarms of bees" buzzing near holes in the ground. These ground nesting bees, flying around a 3- 10' area, are actually one of several species of solitary bees, but dig their tunnels in a "commune" with others of the same species. Within each tunnel, the female will excavate individual chambers, and pack them with pollen and nectar. She then lays an egg in each chamber and seals it. As the larvae grow, they consume the food reserve, then pupate and emerge from the tunnel the following spring. As each successive year progresses, these communes enlarge as more bees return to the site.
The bees most commonly associated with these nests are digger bees (Anthophoridae), sweat bees (Halictidae) and mining bees (Adrenidae). Generally, these bees are hairy and about the size of a honey bee or smaller, although the digger bees are slightly larger and more robust.
Complaints are normally due to the fear of being stung, followed by an annoyance of the bare spot in the yard. Although they may appear menacing with their buzzing and strafing activities, these bees are not aggressive and not likely to sting. Also bear in mind that the bees tunneled in that location because the turf or ground cover was not dense and vigorous.
Control is not recommended since they are great pollinators. After the spring activity has dissipated, the area can be overseeded, sodded, or mulched to provide a more dense cover. If swift relief from the bees is deemed necessary, cover the area temporarily and keep people away.
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ASH BARK BEETLE
One or more species of ash bark beetles (Hylesinus spp.) are found in any given region of the United States. They attack and breed in weakened, storm-damaged, dying, and recently dead, standing trees as well as freshly felled trees and stacks of new firewood. Logs over a year old and those without bark do not support ash bark beetle attacks. Reports of ash bark beetle infestations are usually associated with firewood stored in homes. Given enough time, larvae developing under the bark finish their development and masses of adult beetles emerge from the logs. Hundreds of beetles may emerge from a stack of firewood then fly to nearby windows. Adult beetles are slightly elongate, cylindrical, and 2.0 to 3.4 mm long. Dense areas of light- and dark- colored scales produce mixed bands or spots. Larvae are legless grubs with a white, slightly curved body and a light-brown head. Control of the ash bark beetle is not usually needed. Prevention of indoor problems with ash bark beetles can be accomplished by not storing firewood indoors for extended periods of time.
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DANG THOSE DANGLING CATERPILLARS
Joe Boggs reported that forest tent caterpillars (Malacosoma disstria) are beginning to disperse from their colonies on trees in southwest Ohio. Despite their common name, these caterpillars construct only rudimentary mat like silk nests on leaves or bark. The caterpillars are gregarious during early instar stages. They remain in colonies on twigs and branches during the day and feed on leaves at night. Colonies may contain hundreds of hairy caterpillars and their collective image resembles patches of fur on twigs and branches.
Later instar caterpillars disperse from the colonies and become solitary feeders. During their dispersal, some caterpillars remain on the tree while others elect to rappel on silk threads from their host. Large numbers of dangling hairy caterpillars beneath infested trees can be a serious nuisance. Indeed, Joe noted that he quickly became entangled in silk festooned with suspended caterpillars as he photographed the aerial exodus. Once the soaring caterpillars hit the ground, they begin wandering about in search of food.
Forest tent caterpillars have short grayish-white hairs and distinct white markings running down their backs. These markings have been described as looking like "foot prints" or as being "keyhole shaped." The markings are flanked by cobalt blue lines running the length of the caterpillars' bodies. The caterpillars are sometimes mistaken for other hairy caterpillars such as EASTERN TENT CATERPILLAR (M. americanum) or GYPSY MOTH (Lymantria dispar). Eastern tent caterpillars have a distinct, unbroken white stripe down their backs. Gypsy moth caterpillars have 5 pairs of blue spots followed by 6 pairs of red spots running down their back.
Forest tent caterpillars feed on a wide variety of deciduous trees including oak, ash, sweetgum, birch, cherry, aspen, elm, basswood, and sugar maple. Large well established healthy trees can sustain a considerable amount of defoliation from these early-season caterpillars without suffering long-term ill effects. Such trees can draw upon carbohydrate reserves to produce new leaves. However, young, recently planted trees have fewer reserves and can be severely stressed by heavy defoliation.
Caterpillars in southern Ohio are now too large for the naturally occurring bacterium, Bacillus thuringiensis (Bt), to be effective. Other insecticides labeled for the host must be used. For a list of effective caterpillar insecticides, refer to the OSU Extension Bulletin 504, "Insect and Mite Control on Woody Ornamentals and Herbaceous Perennials" http://ohioline.osu.edu/b504/index.html
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HAWTHORN LEAF GALLS
Joe Boggs noted that hawthorn pod, or cockscomb, galls are becoming very evident on trees in southwest Ohio. The galls are produced by a tiny midge fly and form along the veins on the underside of leaves. Opening the hollow galls will reveal the midge maggots responsible for directing gall development. Currently, the raised galls are light green and smooth. Later, they will become bumpy and red causing them to resemble a cockscomb. The galls restrict normal leaf expansion, and cause leaves to become twisted or curled.
Like all leaf galls, the hawthorn pod galls can only develop on expanding leaves. Once leaves are fully expanded, the galls cannot form. No insecticide recommendations are currently available for this gall-making midge. Populations can be reduced by removing and destroying galled leaves. However, as with most leaf galls, the hawthorn pod galls appear to cause no harm to infested trees other than reducing their aesthetic appearance.
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WINDSHIELD WIPES
BYGLers also ran into a few other insects and this week, including:
* Several BYGLers have reported that GYPSY MOTH (Lymantria dispar) eggs have begun to hatch throughout Ohio, however it is not a synchronous hatch. Egg hatch has disproportionately occurred on surfaces with southern exposures. North-facing egg masses are well behind in their development. Those who are planning suppression spray programs should wait until more of the north-facing egg masses hatch before initiating sprays. It is recommended that applicators monitor egg masses regularly to determine when hatch occurs before spraying commences. A higher impact on gypsy moth populations can be accomplished by waiting until a larger proportion of the eggs have hatched.
* Reports of swarms of wasp-like insects have been observed on tree trunks, wood piles and walls of buildings. Capture and identification of the insects revealed that they were PAINTED HICKORY BORERS (Megacyllene caryae). These beetles are a type of long-horned beetle that attacks hickory, ash, Osage orange and hackberry wood. Adults are 3/4 - 7/8" long, with reddish legs and yellow and black markings, bands and patterns on the body, similar to yellowjacket wasps. Adults are active in the spring. The painted hickory borer is very similar in appearance to the LOCUST BORER (Megacyllene robiniae), but the locust borer adult is only active in the fall. No control measures are necessary for either beetle.
* Dave Shetlar reported that CLOVER MITES (Bryobia praetiosa) are active, and increasing in population. Clover mites are very tiny arachnids that live and reproduce outdoors, but are frequently encountered as a household pest in early summer and in the fall when they migrate into dwellings by mistake. They are only 1/64" long, soft, oval, and flattened from top to bottom. They vary in color from rusty brown to dark red. A distinguishing characteristic is the very long pair of front legs that extend forward like antennae as the mites crawl. It is best to use a perimeter spray barrier around the outside of the house during the mite invasion period. Outdoors, spray the foundation, exterior walls up to the bottom of the first floor windows, and a strip 10' to 20' wide from the foundation out into the grass. Materials that are effective against clover mites include bifenthrin, deltamethrin and lambda-cyhalothrin.
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TURF TIPS
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TURF PESTS UP!
Dr. Shetlar reported that chinch bugs, Ataenius beetles, and billbugs are now active in Central Ohio. At this point, turfgrass managers should have decided which areas warrant control and/or monitoring, after assessing last years insect populations. Several control options are available.
If chinch bugs were present at levels high enough to damage turfgrass last year, consider treating preventively with a labeled pyrethroid (bifenthrin and deltamethrin provide good results) between mid April - early May. Application of the pyrethroid at this time will also control billbug adults and sod webworm larvae.
Imidacloprid (Merit) can be applied from late April - May to control grubs, billbug larvae, and at least suppress chinch bug populations. Beware of the second generation of chinch bugs that may move in from neighboring turfgrass in August-September. Dr. Dave Shetlar's graduate student is discovering that even irrigated lawns can be susceptible to high chinch bug populations.
Ataenius beetles can be managed by treating preventively with imidacloprid or thiamethoxam when the Vanhoutte spirea blooms (early May), or halofenazide in early June.
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THE INVASION HAS BEGUN, DANDELIONS!
Spring has sprung and we are reminded of that fact by the numerous plants that are going through their springtime bloom, including some of the less desirable plants. BYGLers commented on the massive carpets of dandelions that cover home lawns, agriculture fields and turfgrass areas around businesses. Soon these dazzling fields of golden yellow blossoms will be turning into fields of puffball seed heads to spread the dandelions to new locations.
Although the dandelions may be growing actively, many of the other broadleaf weeds in lawns have yet to begin their growth and development for this year. Because of this difference in growth and development of broadleaf weeds, proper timing of broadleaf weed herbicide applications can be a challenge. There is a temptation to apply these herbicides as soon as the dandelions appear, however, if only one application of broadleaf herbicides is going to be applied in the spring/early summer, many of the slower growing broadleaf weeds, such as plantain and ground ivy, will be missed.. Thus, it is recommended that spring applications of broadleaf herbicides be delayed until mid- to late May to allow these other weeds to being growing more actively.
On the other hand, Randy Zondag made a good point that grassy areas with massive populations of dandelions need to be tackled now to reduce the amount of seeds produced, and to reduce the competition of the dandelions with the turfgrass. This action will require a second spring application of broadleaf herbicides later in the spring/early summer, if other weeds are present.
Most of the broadleaf herbicides are formulations of 2,4-D, MCPP, dicamba, MCPA, 2,4-DP or some combination of these products. Read the labels on these products carefully, paying close attention to limits to the number of applications permitted per year, timing of mowing in relation to the timing of application, environmental conditions, and avoidance of runoff into bodies of water. Since applications might be applied in the spring, rotation of active ingredients is suggested. Inclusion of triclopyr in the second application in place of 2,4-D is one suggestion for rotation, however, use formulations of triclopyr which do NOT contain clopyralid, as it can not be used on residential lawns.
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COMING ATTRACTIONS
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UPCOMING OSU EXTENSION PLANT DIAGNOSTIC WORKSHOPS
A number of OSU ENLT Team workshops are scheduled for the season. Topics at each of the workshops this year include the following and more: Emerald Ash Borer, Diseases and Insects du Jour, Dr. Dendro Diagnostic Case Studies, Digital Diagnostics, Clinic Catharsis Sample Sharing, and Diagnostic Walks. As the season progresses, additional topics will be added. A more extensive program will be developed for the two-day October 5-6, 2006 Ohio Plant Diagnostic Workshop for Clinicians.
Dates scheduled include: May 24 - ABE Center, Bowling Green, May 26 - Springfield, June 6 - Burton, June 8 - Wooster, July 10 - Columbus, September 13 - Canfield, and October 5-6 - 50th Ohio Plant Diagnostic Workshop for Clinicians - Wooster.
More details on registration will be included in upcoming BYGLs.
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BYGLIVE IN TOLEDO
On Monday, May 1, OSU Extension at Toledo Botanical Garden will be hosting the first BYGL Diagnostic Walk of the season. We will begin our walk-about at Toledo Botanical Garden at 1:00 pm. Meet at the flagpole outside the Conference Center. If you have any questions, please contact OSU Extension at TBG at 419-578-6783.
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BYGLIVE IN CINCINNATI
The 2nd 2006 BYGLive! Diagnostic Walk-About will be held Monday, May 1, at Spring Grove Cemetery & Arboretum from 12:00 - 3:00 p.m. This monthly hands-on training program focuses on diagnosing plant pest, disease, and physiological problems. A new feature this year is tips on taking digital images, so bring your cameras!
Directions to the meeting location are as follows: Enter Spring Grove Cemetery & Arboretum through the main entrance off Spring Grove Avenue; straight ahead is an underpass - drive through the underpass; turn right at the first intersection; keep to the left and travel approximately 300 yards to the meeting site on the left. For more information, contact Joe Boggs at 513-946-8993.
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SALSA (SECREST ACADEMY FOR LANDSCAPE SCIENCES AND ARTS)
The fourth edition of SALSA commences in May at OSU's Secrest Arboretum at the Ohio Agricultural Research and Development Center in Wooster. It is for individuals with professional or personal interest in an intensive, hands-on landscape learning experience and is a program of Ohio State University's Secrest Arboretum and the OSU Extension Center at Wooster. Faculty for session IV of SALSA are Jim Chatfield, Ken Cochran, Joe Cochran and Erik Draper.
SALSA IV focuses on the following topics: Herbaceous Perennials and Annuals, Disease Management, Insect Identification, Plant Problem Diagnostics, Plant Propagation, and Theme Gardens. SALSA IV involves three full-day sessions on May 15, June 19, and July 17.
SALSA is a learning experience, advancing knowledge of the arts and sciences of landscape horticulture, through linked interactive hands-on programs. SALSA is not a series of isolated single-topic programs, nor it a full-fledged 2- or 4- year degree program. SALSA occupies the landscape between these two...rooted in dedication, blooming with creativity. The cost of SALSA IV is $300.00 for the full three days of programming. This fee includes considerable reference material, gourmet lunches and refreshments. For more information contact Joe Cochran at Secrest Arboretum (330-263-3886; cochran.58@osu.edu
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BYGLOSOPHY
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"A weed is a plant that has mastered every survival skill
except for learning how to grow in rows." - Doug Larson
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